Motor vehicles use several lights mounted externally on the vehicle to indicate information to other drivers and pedestrians. In particular, several lights are generally mounted on the rear end of the vehicle to signal drivers and pedestrians behind the vehicle. Additional lights may be placed on the sides of the vehicle, near the rear, to provide additional signals to drivers behind the vehicle, especially those that might be positioned to the left or right of the vehicle
FIG. 1 illustrates a typical arrangement of signal lights for the rear and rear/side of a motor vehicle, such as a motorcycle. From top to bottom, the indicator lights include a right-side running light 110, a right-tail brake/run light 120, a left-tail brake/run light 130, and a left-side running light 140. The right-side and left-side running lights are powered whenever the vehicle is running, to provide general visibility for the vehicle. Likewise, the right-tail and left-tail brake/run lights are also powered when the vehicle is running. In the pictured arrangement, the right-tail and left-tail lights are dual-filament bulbs—one filament, powered through an intermediate or “low-side” connector pin, is always energized when the vehicle is running. An additional filament, powered through the “high-side” connector pin, is energized when the brakes of the vehicle are activated. Thus, the intensity of the light emitted from the bulb is substantially greater when the brakes are activated.
Bulbs using light-emitting diodes (LEDs) rather than incandescent filaments are becoming increasingly popular, both as factory-installed equipment and as replacement parts for installation into standard sockets. Dual-intensity LED-based bulbs are available, including as replacements for dual-intensity incandescent bulbs. While the internal wiring of these three-terminal devices generally differs from that of incandescent bulbs, the operation is the same: a high-level voltage (e.g. 12 volts) on the “high-side” terminal produces a substantially greater light output than the same voltage applied to the “low-side” terminal.
Certain drivers desire enhanced visibility of their vehicles. This is a particular concern for many motorcycle drivers, as motorcycles are often overlooked by other drivers. Accordingly, improved lighting systems for motor vehicles are needed.